The natural world has done it again, with fungi found to extract cobalt and lithium from waste batteries previously consigned to landfills and incinerators.
Disposing of batteries is rarely the most environmentally friendly of activities, with the materials they are made from often having a long-lasting, damaging effect on the environment.
However, maybe the environment itself can provide the solution to this problem, with a team of researchers suggesting fungi can be used to break up the waste in a safe, manageable fashion.
Old batteries often end up in landfills or incinerators, with high temperatures or “harsh chemicals” used to break them down, leading to dangerous emissions being released into the atmosphere.
Jeffrey Cunningham, of the University of South Florida, the leader on this project, is developing an environmentally safe way to do this with fungi, creating an environment for the work to flow.
“Fungi are a very cheap source of labour,” he points out. “The idea first came from a student who had experience extracting some metals from waste slag left over from smelting operations.
“The demand for lithium is rising rapidly, and it is not sustainable to keep mining new lithium resources.”
Using three strains of fungi – Aspergillus niger, Penicillium simplicissimum and Penicillium chrysogenum – Cunningham and co think they’ve solved the problem.
The team first dismantles the batteries and pulverises the cathodes, before exposing fungus to the remains.
“Fungi naturally generate organic acids, and the acids work to leach out the metals,” said Cunningham.
“Through the interaction of the fungus, acid and pulverised cathode, we can extract the valuable cobalt and lithium,” he said, though the result is the duo tied together in a liquid that is, as yet, inseparable.
“We are aiming to recover nearly all of the original material,” said Cunningham, with further strains of fungi under investigation.
Main mushroom image via Shutterstock